Thursday, July 3, 2008

Rudge, Bike Works NYC, and How To Overhaul a Dura-Ace BB7700 Octalink Bottom Bracket

OH GOD, IT HURTS…

photo by Bike Works NYC

Hi.

That captivating chainwheel belongs to a Rudge cottered crank from the early 1900’s.Rudge was a renowned British bicycle manufacturer of antiquity, or at least of what passes for antiquity in the history of bicycles. Rudge produced all of the parts on its bikes, right down to the bearings, and incorporated the hand logo into most of them, always as elegantly as possible. The origin of the logo itself was the Red Hand of Ulster, which was used, in the manner of an emblem, by British families of Northern Irish origin. If I’ve piqued your curiosity, take a look at this.

I’m using the photo courtesy of the good wrenches at Bike Works NYC, the “Lower East Side Cycling Center,” who collected it and others like it into an archive on their websitethat you’ll have to see to believe. I could provide you with a direct link to the chainwheel archive, which itself is divided into chainrings and chainwheels because, as we all would pretend we knew, they’re not the same, but that would dishonor the way in which both the website and the shop are set up, namely, to browse, and hopefully find what you weren’t looking for. However, I will fold and provide you with this direct link to their chainwheel kaleidoscope .

And of course, if you find yourself on the Lower East Side, stop in. It’s a crazy, classic shop, like Kraynick’s in Pittsburgh, or Citybikes in Portland, that makes you want to browse, sit on the curb with a cup of coffee, or just close your eyes and feel, well…bikey. Track racers and fixed-gear aficionados will feel especially welcome, but trendy wendys beware….

I HAVE A CREAK

Actually, it’s a creak, a click, and an occasional crunch, and it’s my bottom bracket, which I have studiously avoided overhauling for well over a year now, or maybe two, or three….

And all because overhauling a bottom bracket is one of the dirtiest, most painful acts of bike maintenance there is, not to mention that I happen to have one of the only bottom brackets that can make that act even more painful by virtue of its very design: the dreaded Dura-Ace Octalink.

Not the Octalink II, mind you, with its external sealed bearings and proud ways. No, I'm talking about its short-lived predecessor, the Octalink, with its two sets of needle bearings and two sets of ball bearings, all of which have the habit of falling out of their retainers and disappearing forever the moment you open the assembly.

The thing is, Shimano's components are engineed and produced to the tightest tolerances possible, especially at the higher end, which is one of the reasons why I've always used Shimano on my own bikes. The Dura-Ace Octalink bottom bracket is no exception, and when it's properly lubricated, installed, an adjusted, it it allows its rider to stretch maintenance intervals to their breaking point with no conspicuous drop in performance.

Alas, this work can wait no more: yesterday afternoon, after meticulously cleaning and lubing my chain, which is to bike maintenance what paying minimum balances is to credit cards, I placed my hand on my bike and asked it once again if it would turn its cranks for me. And this time, from deep inside, came a tiny reply: “no.” I tried anyway, and the cranks turned a quarter turn halfheartedly, then stopped.

Which puts me in mind of a story my father once told me….

A TALE OF THREE DEGREASERS AND A GREASE

Once upon a time there was a beautiful princess named BB7700. Though of royal birth, BB, like all 7700’s, was given a task to perform, in her case nothing less than the creation of momentum from motion. Though she carried out her task without complaint, and with joy in her heart, she was shunned by the rest of her family, who hated her for her narrow q-factor, and abused her, telling her that she was finicky and refused to adjust despite their best efforts. Finally, she was made to live in darkness, and toil in water, dirt, and grease.

A year passed, or maybe two, or three, and BB’s suffering grew boundless. First her ball bearings roughened in their endless rotations, then her needle bearings, then her spindle, until she was sure her races were damaged beyond repair. Finally, her heart broke, and she seized, and would turn no more. She slept, and dreamt of the day when she would spin again, twirling around and around and around in smoothness and light.

One day, three degreasers of the Finish Line family came riding along. Their names were Citrus, Multi, and Speed Clean, and they were followed by their prince, Teflon-Fortified Synthetic Grease, a tacky fellow, to be sure, but unfailingly smooth. Weary from their journey, they finally came to

THE POINT

What follows here is instructions on how to overhaul a Dura-Ace BB7700 Octalink bottom bracket.

But first, a disclaimer: my intention is to offer my opinion on how to overhaul the above bottom bracket, not on how to extract it, disassemble it, upgrade its bearings to ceramic, reassemble it, or modify it in any way. It’s not because of liability issues or anything like that, just that overhauling it is already more than enough for this post. It’s work you have to obsess over, because even though the bottom bracket sees the highest stresses at the highest frequencies in the dirtiest conditions of all the parts on a bike, the time and effort required to extract it mean that it also gets the least maintenance.

And that’s too bad, because a dirty, poorly adjusted bottom bracket can create massive amounts of drag. Even if you have a sealed bearing bottom bracket like the Octalink II, you should overhaul it regularly, as described in the instructions for overhauling a sealed bearing I provided in my June post.

Anyway, because it’s work you have to obsess over, and because this bottom bracket in particular consists of many different parts made with different materials, I feel the use of all three Finish Line degreasers is justified, because they actually take care of things more efficiently than any one of them alone, and they work together to provide the best results.

To begin with – and this the only thing I’ll say about extracting the bottom bracket – always make sure to clean out the splines on the bottom bracket lockrings and cups, as well as the splines on the bottom bracket tool:

Bottom brackets can be almost impossible to extract, and often require considerable leverage to crack free. If the splines on the bottom bracket and the tool are dirty, you run the risk of the tool slipping under torque and absolutely destroying the splines, and with them any hope of extracting the bottom bracket without considerable cost and effort. This is true even if you use one of the many improvised tools at your disposal to keep the tool in place on the splines.

With that said, let’s put on some soothing music and get started. By the way, I don’t mention it in the instructions, but the stiff wire brush I use to clean out the cups and the races is part of Finish Line’s superlativeBrush Set, which I love and use all the time, especially during ‘cross season.

The Scribd player below contains my instructions in the form of a Powerpoint 07 presentation (.pptx), though you don't need Powerpoint to view it. You can view it as a slide show, book, or in tiles, you can zoom in or out, and you can view it full screen, though when you're done viewing it in full screeen, you'll need to click the back button on your browser to return to this post. If you really like it, you can go to Scribd's website and download it for your own use.

And Princess BB7700 and Prince Teflon-Fortified Synthetic Grease were married and spent the rest of their days spinning blissfully ever after.

IN CONCLUSION

To end with – and this is the only thing I’ll say about reinstalling the bottom bracket – use Finish Line Antiseize Assembly Lube when reinstalling the bottom bracket, instead of grease, Permatex, or Teflon plumber’s tape, all of which work, sort of, but not as well. Use gloves, and apply it to the threads in the bottom bracket shell instead of the threads on the cups, because it’ll make less of a mess, and believe me when I say you don’t want to get this on your hands, because it’ll get on everything you touch, though it does glitter and look pretty. If you’re using one of the tubes, squirt it directly on the shell threads, then use a piece of cable housing to swirl it around and distribute it all around the threads. If you're using the can, you're all taken care of, because it comes with a brush attached to the cap.

FULL CIRCLE

You know who else likes Finish Line Antiseize Assembly Lube? Arone Dyer, the New Voice of Bike Repair in the cycling industry. At least she claims to like it in her article in Bicycling magazine..

And do you know where Ms. Dyer works when she’s not writing about Finish Line Antiseize Assembly Lube in Bicycling? Bike Works NYC.

And the chainwheel turns round and round and round….

Incidentally, that really was my bottom bracket, and I really did overhaul it, and I really did just put it back into my bike to the sounds of trumpets and swallows. There are clouds creaming on the western horizon. I’m going to ride toward them and see where that takes me.

The hollow spindle has a slight offset, as measured from the ball race to the edge of the spline, about 1mm difference for one side. However, L<-->R is indicted by a decal that immediately falls off, lol. So my question, which way does the offset go? Any idea?